1. Field of the Invention
The present invention relates to a system and method for broadcasting information, such as Internet web pages, over a networked distribution system, such as a cable television distribution system.
2. Description of the Background Art
U.S. Pat. No. 5,961,603, issued Oct. 5, 1999, U.S. Pat. No. 5,999,979, issued Dec. 7, 1999, and U.S. Pat. No. 6,049,539, issued Apr. 11, 2000, all of which are hereby incorporated by reference, disclose systems and methods for providing interactive access to an information source, such as the Internet, through a networked distribution system, such as a cable television distribution system. In a conventional cable television distribution system, video programming originating from remote and local sources is broadcast from a cable headend, through a plurality of downstream channels to a set top converter box (set top) located at each user's premises. The set top interfaces the received programming to the user's television or monitor, and includes a tuner that is used to select the channel to be viewed, typically by receiving commands from a remote control operated by the user. In the system disclosed in the '603 patent, a cable television user who is a subscriber to a special Internet access service, can access Internet web pages that are related to the present programming content of a cable television channel being viewed by the user. This technique is referred to as CHANNEL HYPERLINKING. In addition, the user can “surf” the Internet in a conventional manner with this system.
In the preferred embodiment disclosed in the '603 patent, the cable television distribution system includes a number of modifications for processing hyperlinking requests from the users. First, at least one upstream channel is provided between each user and the cable headend so that a user can enter hyperlinking requests into their set top, and forward them to the cable headend for processing. The cable headend processes each request by accessing a hyperlink database containing URL's (web addresses) of programming-content related Internet web pages, and retrieving a URL that has been assigned to the channel that the user is viewing for the time period during which the request is made. The cable headend then retrieves the web page from the Internet, or from memory, with an Internet browser application located in the headend, and downloads the web page to the user for viewing. As an example, the user, who may be viewing a television advertisement for a particular product, can thus hyperlink to a web page for that product with this system.
The preferred embodiment of the channel hyperlinking system disclosed in the '603 patent thus provides a convenient technique for enabling users to access additional information that is related to the content of the program they are currently viewing, by simply pressing a button on their remote control. However, the preferred embodiment is not designed for use with cable systems that provide only one-way communication between the cable headend and the system users, since the upstream channel is necessary to send channel hyperlinking requests to the headend.
Another feature that would be desirable in a channel hyperlinking system is “picture-in-picture” capability, wherein a user can simultaneously view both a broadcast television program and a content related web page, for example, so that they can continue watching television while interacting with a channel hyperlink, or conducting an Internet session. For example, the television program could be a scaled image within the web page, or vice versa. Picture-in-picture is easy to provide in a two-tuner set top where one tuner receives the video program, while the other tuner receives the channel hyperlink data. However, the typical set top only has a single in-band tuner that can be used for either video or data.